Troubleshooting and Maintenance...Troubleshooting and Maintenance • TroubleshootingandMaintenanceOverview,page1 • Troubleshooting,page1 • Maintenance,page23 Troubleshooting …

Troubleshooting and Maintenance

• Troubleshooting and Maintenance Overview, page 1

• Troubleshooting, page 1

• Maintenance, page 23

Troubleshooting and Maintenance OverviewThis chapter provides information that can assist you in troubleshooting problems with your Cisco UnifiedIP Phone or with your IP telephony network. It also explains how to clean and maintain your phone.

For additional troubleshooting information, see the Using the 79xx Status Information For Troubleshootingtech note. That document is available to registered Cisco.com users at this URL:

http://www.cisco.com/en/US/products/hw/phones/ps379/products_tech_note09186a00800945bd.shtml

TroubleshootingThis section contains the following topics.

Startup ProblemsAfter installing a Cisco Unified IP Phone into your network and adding it to Cisco Unified CommunicationsManager, the phone should start up as described in the Phone Startup Process Verification. If the phone doesnot start up properly, see the following sections for troubleshooting information.

Cisco Unified IP Phone Does Not Go Through Normal Startup Process

Problem

When you connect a Cisco Unified IP Phone into the network port, the phone should go through its normalstartup process and the LCD screen should display information.

Cisco Unified IP Phone 7941G, 7941G-GE, 7942G, 7961G, 7961G-GE, and 7962G Administration Guide for Cisco UnifiedCommunications Manager 9.0 (SCCP and SIP)

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http://www.cisco.com/en/US/products/hw/phones/ps379/products_tech_note09186a00800945bd.shtml

P746_BK_IC15BCED_00_adminguide-7941g-7941g-ge-7942-7961g-7961g-ge-7962g_chapter_011.pdf#unique_84

Cause

If the phone does not go through the startup process, the cause may be faulty cables, bad connections, networkoutages, lack of power, or the phone may not be functional.

Solution

The following suggestions can help determine if the phone is functional:

1 Verify that the network port is functional:

• Exchange the Ethernet cables with cables that you know are functional.

• Disconnect a functioning Cisco Unified IP Phone from another port and connect it to this networkport to verify the port is active.

• Connect the Cisco Unified IP Phone that will not start up to a different network port that is knownto be good.

• Connect the Cisco Unified IP Phone that will not start up directly to the port on the switch, eliminatingthe patch panel connection in the office.

2 Verify that the phone is receiving power:

• If you are using external power, verify that the electrical outlet is functional.

• If you are using in-line power, use the external power supply instead.

• If you are using the external power supply, switch with a unit that you know to be functional.

3 If the phone still does not start up properly, power up the phone with the handset off-hook. When thephone is powered up in this way, it attempts to launch a backup software image.

4 If the phone still does not start up properly, perform a factory reset of the phone. For instructions, seePerform Factory Reset, on page 22.

If after attempting these solutions, the LCD screen on the Cisco Unified IP Phone does not display anycharacters after at least five minutes, contact a Cisco technical support representative for additional assistance.

Cisco Unified IP Phone Does not Register with Cisco Unified Communications ManagerIf the phone proceeds past the first stage of the startup process (LED buttons flashing on and off) but continuesto cycle through the messages displaying on the LCD screen, the phone is not starting up properly. The phonecannot successfully start up unless it is connected to the Ethernet network and it has registered with aCisco Unified Communications Manager server.

In addition, problems with security may prevent the phone from starting up properly. See Cisco Unified IPPhone Security Problems, on page 8 for more information.

Phone Displays Error Messages

Problem

Status messages display errors during startup.

Cisco Unified IP Phone 7941G, 7941G-GE, 7942G, 7961G, 7961G-GE, and 7962G Administration Guide for CiscoUnified Communications Manager 9.0 (SCCP and SIP)

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Troubleshooting and MaintenanceStartup Problems

Solution

As the phone cycles through the startup process, you can access status messages that might provide you withinformation about the cause of a problem. See Status Messages Screen for instructions about accessing statusmessages and for a list of potential errors, their explanations, and their solutions.

Phone Cannot Connect to TFTP Server or to Cisco Unified Communications Manager

Problem

If the network is down between the phone and either the TFTP server or Cisco Unified CommunicationsManager, the phone cannot start up properly.

Solution

Ensure that the network is currently running.

TFTP Server Settings

Problem

The TFTP server settings may not be correct.

Solution

Check the TFTP settings. See Check TFTP Settings, on page 15.

IP Address and Routing

Problem

The IP addressing and routing fields may not be correctly configured.

Solution

You should verify the IP addressing and routing settings on the phone. If you are using DHCP, the DHCPserver should provide these values. If you have assigned a static IP address to the phone, you must enter thesevalues manually. See Check DHCP Settings, on page 15.

DNS Settings

Problem

The DNS settings may be incorrect.

Solution

If you are using DNS to see the TFTP server or to Cisco Unified Communications Manager, you must ensurethat you have specified a DNS server. See Verify DNS Settings, on page 15.


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Cisco Unified Communications Manager Settings On Phone

Problem

The phone may have the correct Cisco Unified Communications Manager information.

Solution

On the Cisco Unified IP Phone, press the Settings button, choose Device Configuration, and look at theUnified CM Configuration options. The Cisco Unified IP Phone attempts to open a TCP connection to allthe CiscoUnified CommunicationsManager servers that are part of the assigned CiscoUnified CommunicationsManager group. If none of these options contain IP addresses or show Active or Standby, the phone is notproperly registered with Cisco Unified CommunicationsManager. See Phone Cannot Connect to TFTP Serveror to Cisco Unified Communications Manager, on page 3 for tips on resolving this problem.

Cisco CallManager and TFTP Services Are Not Running

Problem

If the Cisco CallManager or TFTP services are not running, phones may not be able to start up properly. Insuch a situation, it is likely that you are experiencing a systemwide failure, and other phones and devices areunable to start up properly.

Solution

If the Cisco CallManager service is not running, all devices on the network that rely on it to make phone callsare affected. If the TFTP service is not running, many devices cannot start up successfully. For moreinformation, see Start Service, on page 16.

Configuration File Corruption

Problem

If you continue to have problems with a particular phone that other suggestions in this chapter do not resolve,the configuration file may be corrupted.

Solution

Create a new phone configuration file. See Create New Phone Configuration File, on page 16.

Cisco Unified Communications Manager Phone Registration

Problem

The phone is not registered with the Cisco Unified Communications Manager

Solution

A Cisco Unified IP Phone can register with a Cisco Unified Communications Manager server only if thephone has been added to the server or if auto-registration is enabled. Review the information and procedures


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in Cisco Unified CommunicationsManager Phone AdditionMethods to ensure that the phone has been addedto the Cisco Unified Communications Manager database.

To verify that the phone is in the Cisco Unified Communications Manager database, choose Device > Phone> Find from Cisco Unified Communications Manager Administration to search for the phone based on itsMACAddress. For information about determining aMAC address, see Cisco Unified IP PhoneMACAddressDetermination.

If the phone is already in the Cisco Unified Communications Manager database, its configuration file may bedamaged. See Configuration File Corruption, on page 4 for assistance.

Cisco Unified IP Phone Cannot Obtain IP Address

Problem

If a phone cannot obtain an IP address when it starts up, the phone may not be on the same network or VLANas the DHCP server, or the switch port to which the phone connects may be disabled.

Solution

Ensure that the network or VLAN to which the phone connects has access to the DHCP server, and ensurethat the switch port is enabled.

Cisco Unified IP Phone Displays Security Error Message

Problem

The phone displays Security Error on the screen.

Cause

When a Cisco Unified IP Phone boots, it performs an internal Power On Self Test (POST). POST checks forexisting encryption functionality. If POST detects that encryption functionality is missing, the phone fails toboot, and the message “Security Error” appears on the screen.

Solution

To correct the problem, perform the following steps:

1 Reset the phone manually.

2 If the phone does not start up properly, power up the phone with the handset off-hook. When the phoneis powered up in this way, it attempts to launch a backup software image.

3 If the phone still does not start up properly, perform a factory reset of the phone. For instructions, seePerform Factory Reset, on page 22.

Cisco Unified IP Phone Resets UnexpectedlyIf users report that their phones are resetting during calls or while idle on their desk, you should investigatethe cause. If the network connection and Cisco Unified Communications Manager connection are stable, aCisco Unified IP Phone should not reset on its own.


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Troubleshooting and MaintenanceCisco Unified IP Phone Resets Unexpectedly




A phone resets if it has problems connecting to the Ethernet network or to Cisco Unified CommunicationsManager.

Physical Connection Problems

Problem

The physical connection to the LAN may be broken.

Solution

Verify that the Ethernet connection to which the Cisco Unified IP Phone connects is up. For example, checkwhether the particular port or switch to which the phone connects is down and that the switch is not rebooting.Also ensure that no cable breaks exist.

Intermittent Network Outages

Problem

Your network may be experiencing intermittent outages.

Solution

Intermittent network outages affect data and voice traffic differently. Your network might be experiencingintermittent outages without detection. If so, data traffic can resend lost packets and verify that packets arereceived and transmitted. However, voice traffic cannot recapture lost packets. Rather than retransmitting alost network connection, the phone resets and attempts to reconnect to the network. Contact the systemadministrator for information on known problems in the voice network.

DHCP Setting Errors

Problem

The DHCP settings may be incorrect.

Solution

The following suggestions can help you determine if the phone has been properly configured to use DHCP:

1 Verify that you have properly configured the phone to use DHCP. See Network Configuration Menu formore information.

2 Verify that the DHCP server has been set up properly.

3 Verify the DHCP lease duration. We recommend that you set the lease duration to 8 days.

Cisco Unified IP Phones send messages with request type 151 to renew their DHCP address leases. If theDHCP server expects messages with request type 150, the lease renewal is denied, forcing the phone to restartand request a new IP address from the DHCP server.


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Static IP Address Setting Errors

Problem

The static IP address assigned to the phone may be incorrect.

Solution

If the phone has been assigned a static IP address, verify that you have entered the correct settings.

Voice VLAN Setup Errors

Problem

If the Cisco Unified IP Phone appears to reset during heavy network usage (for example, following extensiveweb surfing on a computer connected to same switch as phone), it is likely that you do not have a voice VLANconfigured.

Solution

Isolating the phones on a separate auxiliary VLAN increases the quality of the voice traffic.

Phones Have Not Been Intentionally Reset

Problem

If you are not the only administrator with access to Cisco Unified Communications Manager, you shouldverify that no one else has intentionally reset the phones.

Solution

You can check whether a Cisco Unified IP Phone received a command from Cisco Unified CommunicationsManager to reset by pressing the Applications Menu button on the phone and choosing Settings > Status >Network Statistics. If the phone was recently reset one of these messages appears:

• Reset-Reset: Phone received a Reset-Reset request from Cisco Unified Communications ManagerAdministration.

• Reset-Restart: Phone received a Reset-Restart request from Cisco Unified Communications ManagerAdministration.

DNS or Other Connectivity Errors

Problem

The phone reset continues and you suspect DNS or other connectivity issues.


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Solution

If the phone continues to reset, eliminate DNS or other connectivity errors with Determine DNS or ConnectivityIssues, on page 17.

Power Connection Problems

Problem

The phone does not appear to be powered up.

Solution

In most cases, a phone restarts if it powers up by using external power but loses that connection and switchesto PoE. Similarly, a phone may restart if it powers up by using PoE and then connects to an external powersupply.

Cisco Unified IP Phone Security ProblemsThe following sections provide troubleshooting information for the security features on the Cisco Unified IPPhone. For information about the solutions for any of these issues, and for additional troubleshootinginformation about security, see Cisco Unified Communications Manager Security Guide.

CTL File ProblemsThe following sections describe problems with the CTL file:

Authentication Error, Phone Cannot Authenticate CTL File

Problem

A device authentication error occurs.

Cause

CTL file does not have a Cisco Unified Communications Manager certificate or has an incorrect certificate.

Solution

Install a correct certificate.

Phone Cannot Authenticate CTL File

Problem

Phone cannot authenticate the CTL file.

Cause

The security token that signed the updated CTL file does not exist in the CTL file on the phone.


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Troubleshooting and MaintenanceCisco Unified IP Phone Security Problems

Solution

Change the security token in the CTL file and install the new file on the phone.

CTL File Authenticates but Other Configuration Files Do Not Authenticate

Problem

Phone cannot authenticate any configuration files other than the CTL file.

Cause

A bad TFTP record exists, or the configuration file may not be signed by the corresponding certificate in thephone Trust List.

Solution

Check the TFTP record and the certificate in the Trust List.

ITL File Authenticates but Other Configuration Files Do Not Authenticate

Problem

Phone cannot authenticate any configuration files other than the ITL file.

Cause

The configuration file may not be signed by the corresponding certificate in the phone Trust List.

Solution

Re-sign the configuration file by using the correct certificate.

Phone Does Not Register

Problem

Phone does not register with Cisco Unified Communications Manager.

Cause

The CTL file does not contain the correct information for the Cisco Unified CommunicationsManager server.

Solution

Change the Cisco Unified Communications Manager server information in the CTL file.

Signed Configuration Files Are Not Requested

Problem

Phone does not request signed configuration files.


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Cause

The CTL file does not contain any TFTP entries with certificates.

Solution

Configure TFTP entries with certificates in the CTL file.

802.1X Authentication Problems802.1X authentication problems can be broken down into the categories described in the following table:

SeeIf all the following conditions apply,

802.1X Enabled on Phone but Phone Does Not Authenticate• Phone cannot obtain a DHCP-assignedIP address

• Phone does not register with CiscoUnified Communications Manager

• Phone status display as Configuring IPor Registering

• 802.1X Authentication Status displaysas Held (see 802.1X Authentication andStatus).

• Status menu displays 802.1x status asFailed (see Call Statistics Screen).

802.1X Not Enabled• Phone cannot obtain a DHCP-assignedIP address



• 802.1X Authentication Status displaysas Disabled (see 802.1X Authenticationand Status).

• Status menu displays DHCP status astiming out (see Call Statistics Screen).


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SeeIf all the following conditions apply,

Factory Reset of Phone has Deleted 802.1X Shared Secret• Phone cannot obtain a DHCP-assignedIP address



• Cannot access phone menus to verify802.1X status

802.1X Enabled on Phone but Phone Does Not Authenticate

Problem

The phone cannot authenticate.

Cause

These errors typically indicate that 802.1X is enabled on the phone, but the phone is unable to authenticate.

Solution

1 Verify that you have properly configured the required components. See 802.1X Authentication for moreinformation

2 Confirm that the shared secret is configured on the phone. See Security Configuration Menu for moreinformation.

• If the shared secret is configured, verify that you have the same shared secret entered on theauthentication server.

• If the shared secret is not configured, enter it, and ensure that it matches the shared secret on theauthentication server.

802.1X Not Enabled

Problem

The phone does not have 802.1X configured.

Cause

These errors typically indicate that 802.1X is not enabled on the phone.


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Solution

To enable it, see Security Configuration Menu for information on enabling 802.1X on the phone.

Factory Reset of Phone has Deleted 802.1X Shared Secret

Problem

After a reset, the phone does not authenticate.

Cause

These errors typically indicate that the phone has completed a factory reset while 802.1X was enabled. Afactory reset deletes the shared secret, which is required for 802.1X authentication and network access.

Solution

To resolve this, you have two options:

• Temporarily disable 802.1X on the switch.

• Temporarily move the phone to a network environment that is not using 802.1X authentication.

After the phone starts up normally in one of these conditions, you can access the 802.1X configuration menusand re-enter the shared secret.

Audio and Video ProblemsThe following sections describe how to resolve audio and video problems.

Phone Display Is Wavy

Problem

The display appears to have rolling lines or a wavy pattern.

Cause

The phone might be interacting with certain types of older fluorescent lights in the building.

Solution

Move the phone away from the lights or replace the lights to resolve the problem.

No Speech Path

Problem

One or more people on a call do not hear any audio.


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Troubleshooting and MaintenanceAudio and Video Problems


Solution

When at least one person in a call does not receive audio, IP connectivity between phones is not established.Check the configuration of routers and switches to ensure that IP connectivity is properly configured.

General Telephone Call ProblemsThe following sections help troubleshoot general telephone call problems.

VPN-Connected Phone Does Not Log Calls

Problem

A remote location (home office) phone that is connected through the VPN does not log missed, placed, orreceived calls.

Cause

Without explicitly setting the Alternate TFTP setting, the Cisco IP Phone cannot contact the TFTP server anddownload the configuration and other files, and function properly.

Solution

Set up the phone to use the Alternate TFTP server and configure the TFTP server IP address.

Related Topics

Set Up Remote Phone, on page 14

Phone Does Not Recognize DTMF Digits or Digits Are Delayed

Problem

The user complains that numbers are missed or delayed when the keypad is used.

Cause

Pressing the keys too quickly can result in missed or delayed digits.

Solution

Keys should not be pressed rapidly.

Phone Call Cannot Be Established

Problem

A user complains about not being able to make a call.


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Troubleshooting and MaintenanceGeneral Telephone Call Problems

Cause

The phone does not have a DHCP IP address, is unable to register to Cisco Unified CommunicationsManager.Phones with an LCD display show the message Configuring IP or Registering. Phones without anLCD display play the reorder tone (instead of dial tone) in the handset when the user attempts to make a call.

Solution

1 Verify the following:

a The Ethernet cable is attached.b The Cisco CallManager service is running on the Cisco Unified Communications Manager server.c Both phones are registered to the same Cisco Unified Communications Manager.

2 Audio server debug and capture logs are enabled for both phones. If needed, enable Java debug.

Troubleshooting ProceduresThese procedures can be used to identify and correct problems.

Set Up Remote PhoneCisco IP Phones that are configured for SSL VPN to ASA using the built-in client in a remote location (forexample, a home office) have a special configuration requirement.

We recommend that you provide the phone with an Alternate TFTP server setting manually. This settingallows the phone to download the configuration and other files from TFTP. The phone in a remote location(home office) cannot correctly provide OPTION 150 to the phone using DHCP.

The IP phone can register to the last-known Cisco Unified Communications Manager, but any configurationupdates cannot applied until you configure the manual TFTP server address.

Procedure

Step 1 On the phone, select Applications.Step 2 Navigate to the IPv4 Settings window.Step 3 Scroll to the Alternate TFTP option and set the field to Yes.Step 4 In the TFTP Server 1 field, set the TFTP server address.Step 5 Save the changes.


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Troubleshooting and MaintenanceTroubleshooting Procedures

Check TFTP Settings

Procedure

Step 1 You can determine the IP address of the TFTP server used by the phone by pressing Settings, choosingNetwork Configuration > IPv4 and scrolling to the TFTP Server 1 option.

Step 2 If you have assigned a static IP address to the phone, you must manually enter a setting for the TFTP Server1 option. See Network Configuration Menu.

Step 3 If you are using DHCP, the phone obtains the address for the TFTP server from the DHCP server. Check theIP address configured in Option 150.

Step 4 You can also enable the phone to use an alternate TFTP server. Such a setting is particularly useful if thephone was recently moved from one location to another. See Network Configuration Menu for instructions.

Check DHCP Settings

Procedure

Step 1 On the Cisco Unified IP Phone, choose Settings >Network Configuration > IPv4 Configuration, and lookat the following options:

• DHCP Server: If you have assigned a static IP address to the phone, you do not need to enter a valuefor the DHCP Server option. However, if you are using a DHCP server, this option must have a value.If it does not, check your IP routing and VLAN configuration. See the Troubleshooting Switch Port andInterface Problems document, available at this URL :

http://www.cisco.com/en/US/products/hw/switches/ps708/prod_tech_notes_list.html

• IP Address, Subnet Mask, Default Router: If you have assigned a static IP address to the phone, youmust manually enter settings for these options. See Network Configuration Menu for instructions.

Step 2 If you are using DHCP, check the IP addresses distributed by your DHCP server. See the Understanding andTroubleshooting DHCP in Catalyst Switch or Enterprise Networks document, available at this URL: http://www.cisco.com/en/US/tech/tk648/tk361/tech_tech_notes_list.html

Verify DNS SettingsTo verify DNS settings, perform these steps.


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http://www.cisco.com/en/US/products/hw/switches/ps708/prod_tech_notes_list.html


http://www.cisco.com/en/US/tech/tk648/tk361/tech_tech_notes_list.html

http://www.cisco.com/en/US/tech/tk648/tk361/tech_tech_notes_list.html

Procedure

Step 1 Verify this setting by pressing Settings.Step 2 Choose Network Configuration and scroll to the DNS Server 1 option.Step 3 Verify that a CNAME entry exists in the DNS server for the TFTP server and for the

Cisco Unified Communications Manager system.Step 4 Ensure that DNS is configured to do reverse look-ups.

Start Service

A service must be activated before it can be started or stopped. To activate a service, choose Tools >Service Activation.

Note

To start a service, follow these steps:

Procedure

Step 1 From Cisco Unified Communications Manager Administration, choose Cisco Unified Serviceability fromthe Navigation drop-down list and click Go.

Step 2 Choose Tools > Control Center - Feature Services.Step 3 Choose the primary Cisco Unified Communications Manager server from the Server drop-down list.

The window displays the service names for the server that you chose, the status of the services, and a servicecontrol panel to start or stop a service.

Step 4 If a service has stopped, click the corresponding radio button and then click Start.The Service Status symbol changes from a square to an arrow.

Create New Phone Configuration FileIf you continue to have problems with a particular phone that other suggestions in this chapter do not resolve,the configuration file may be corrupted.


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Note • When you remove a phone from the Cisco Unified Communications Manager database, itsconfiguration file is deleted from the Cisco Unified Communications Manager TFTP server. Thephone’s directory number or numbers remain in the CiscoUnified CommunicationsManager database.They are called “unassigned DNs” and can be used for other devices. If unassigned DNs are not usedby other devices, delete them from the Cisco Unified Communications Manager database. You canuse the Route Plan Report to view and delete unassigned reference numbers. See CiscoUnified Communications Manager Administration Guide for more information.

• Changing the buttons on a phone button template, or assigning a different phone button template toa phone, may result in directory numbers that are no longer accessible from the phone. The directorynumbers are still assigned to the phone in the Cisco Unified Communications Manager database,but there is no button on the phone with which calls can be answered. These directory numbersshould be removed from the phone and deleted if necessary.

To create a new configuration file, follow these steps:

Procedure

Step 1 FromCiscoUnified CommunicationsManager, chooseDevice >Phone >Find to locate the phone experiencingproblems.

Step 2 Choose Delete to remove the phone from the Cisco Unified Communications Manager database.Step 3 Add the phone back to the Cisco Unified Communications Manager database. See Cisco Unified

Communications Manager Phone Addition Methods for details.Step 4 Power cycle the phone.

Determine DNS or Connectivity IssuesIf the phone continues to reset, follow these steps to eliminate DNS or other connectivity errors:

Procedure

Step 1 Use Erase to reset phone settings to their default values. See Cisco Unified IP Phone Reset or Restore, onpage 21 for details.

Step 2 Modify DHCP and IP settings:a) Disable DHCP. See Network Configuration Menu for instructions.b) Assign static IP values to the phone. See Network Configuration Menu for instructions. Use the same

default router setting used for other functioning Cisco Unified IP Phones.


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c) Assign a TFTP server. See Network Configuration Menu for instructions. Use the same TFTP server usedfor other functioning Cisco Unified IP Phones.

Step 3 On the Cisco Unified Communications Manager server, verify that the local host files have the correctCisco Unified Communications Manager server name mapped to the correct IP address.

Step 4 From Cisco Unified Communications Manager, choose System > Server and verify that the server is referredto by its IP address and not by its DNS name.

Step 5 From Cisco Unified Communications Manager, choose Device > Phone > Find and verify that you haveassigned the correct MAC address to this Cisco Unified IP Phone. For information about determining a MACaddress, see Cisco Unified IP Phone MAC Address Determination.

Step 6 Power cycle the phone.

General Troubleshooting InformationThe following table provides general troubleshooting information for the Cisco Unified IP Phone.

Table 1: Cisco Unified IP Phone Troubleshooting

ExplanationSummary

Cisco does not support connecting an IP Phone to another IP Phonethrough the PC port. Each IP Phone should directly connect to aswitch port. If phones are connected together in a line using the PCport, the phones will not work.

Connecting a Cisco Unified IP Phoneto another Cisco Unified IP Phone

In Cisco Unified Communications Manager, you can configure thenetwork to use the G.729 protocol. The default protocol is G.711.When using G.729, calls between an IP Phone and a digital cellularphone will have poor voice quality. Use G.729 only when absolutelynecessary.

Poor quality when calling digital cellphones using the G.729 protocol

A prolonged Layer 2 broadcast storm lasting several minutes onthe voice VLAN may cause IP Phones to reset, lose an active call,or be unable to initiate or answer a call. Phones may not come upuntil a broadcast storm ends.

Prolonged broadcast storms causeIP phones to reset, or be unable to makeor answer a call

If you are powering your phone through the network connection,you must be careful if you decide to unplug the phone’s networkconnection and plug the cable into a desktop computer.

The network card in the computer cannot receive powerthrough the network connection; if power comes throughthe connection, the network card can be destroyed. Toprotect a network card, wait 10 seconds or longer afterunplugging the cable from the phone before plugging itinto a computer. This delay gives the switch enoughtime to recognize that there is no longer a phone on theline and to stop providing power to the cable.

Caution

Moving a network connection from thephone to a workstation


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Troubleshooting and MaintenanceGeneral Troubleshooting Information



ExplanationSummary

By default, the network configuration options are locked to preventusers from making changes that could impact their networkconnectivity. You must unlock the network configuration optionsbefore you can configure them. See Unlock and Lock Options fordetails.

Changing the telephone configuration

The phone resets when it loses contact with the CiscoUnified Communications Manager software. This lost connectioncan be due to any network connectivity disruption, including cablebreaks, switch outages, and switch reboots.

Phone resetting

The RxType and the TxType statistics show the codec that is beingused for a conversation between this Cisco Unified IP phone andthe other device. The values of these statistics should match. If theydo not, verify that the other device can handle the codecconversation, or that a transcoder is in place to handle the service.

See Call Statistics Screen for information about displaying thesestatistics.

Codec mismatch between the phoneand another device

The RxSize and the TxSize statistics show the size of the voicepackets that are being used in a conversation between this CiscoUnified IP phone and the other device. The values of these statisticsshould match.


Sound sample mismatch between thephone and another device

Check the AvgJtr and theMaxJtr statistics. A large variance betweenthese statistics might indicate a problem with jitter on the networkor periodic high rates of network activity.


Gaps in voice calls

A loopback condition can occur when the following conditions aremet:

• The SW Port Configuration option in the NetworkConfiguration menu on the phone is set to 10 Half (10-BaseT/ half duplex)

• The phone receives power from an external power supply

• The phone is powered down or the power supply isdisconnected

In this case, the switch port on the phone can become disabled andthe following message appears in the switch console log:

HALF_DUX_COLLISION_EXCEED_THRESHOLD

To resolve this problem, re-enable the port from the switch.

Loopback condition


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ExplanationSummary

If the Peer Firmware Sharing fails, the phone will default to usingthe TFTP server to download firmware. Access the log messagesstored on the remote logging machine to help debug the PeerFirmware Sharing feature.

These log messages are different from the log messagessent to the phone log.

Note

Peer Firmware Sharing fails.

If you are having problems getting CVTA to work, make sure thatthe PC Port is enabled, and that CDP is enabled on the PC port.

See Network Configuration Menu for more information.

Cisco VT Advantage/Unified VideoAdvantage (CVTA)

The phone does not have a DHCP IP address, is unable to registerto Cisco Unified Communications Manager, and shows aConfiguring IP or Registering message.

Verify the following:

1 The Ethernet cable is attached.

2 The Cisco CallManager service is running on the Cisco UnifiedCommunications Manager server.

3 Both phones are registered to the same Cisco UnifiedCommunications Manager.

4 Audio server debug and capture logs are enabled for bothphones. If needed, enable Java debug.

Phone call cannot be established

Call statistics display does not show iLBC as the receiver/sendercodec.

1 Check the following by using Cisco Unified CommunicationsManager Administration:

• Both phones are in the iLBC device pool.

• The iLBC device pool is configured with the iLBC region.

• The iLBC region is configured with the iLBC codec.

2 Capture a sniffer trace between the phone and Cisco UnifiedCommunications Manager and verify that SCCP messages,OpenReceiveChannel, and StationMediaTransmit messageshave media payload type value equal to 86. If so, the problemis with the phone; otherwise, the problem is with the CiscoUnified Communications Manager configuration.

3 Enable audio server debug and capture logs from both phones.If needed, enable Java debug.

Call established with the iLBC protocoldoes not show that the iLBC codec isbeing used


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General Troubleshooting Tips for Cisco Unified IP Phone Expansion ModuleThe following table provides general troubleshooting information for the Cisco Unified IP Phone ExpansionModule.

Table 2: Cisco Unified IP Phone Expansion Module Troubleshooting

SolutionProblem

Verify that all of the cable connections are correct.

Verify that you have power to the Cisco Unified IP Phone ExpansionModule.

No display on the CiscoUnified IP Phone Expansion Module.

Verify that the Cisco Unified IP Phone Expansion Module isconfigured in Cisco Unified Communications Manager.

Lighted buttons on the first CiscoUnified IP Phone Expansion Moduleare all red.

Verify that the Cisco Unified IP Phone Expansion Module isconfigured in Cisco Unified Communications Manager.

Lighted buttons on the second CiscoUnified IP Phone Expansion Moduleare all amber.

Cisco Unified IP Phone Reset or RestoreThere are two general methods for resetting or restoring the Cisco Unified IP Phone.

Basic ResetPerforming a basic reset of a Cisco Unified IP Phone provides a way to recover if the phone experiences anerror and provides a way to reset or restore various configuration and security settings.

The following table describes the ways to perform a basic reset. You can reset a phone with any of theseoperations after the phone has started up. Choose the operation that is appropriate for your situation.

Table 3: Basic Reset Methods

ExplanationPerformingOperation

Resets any user and network configurationchanges that you have made, but that thephone has not written to its Flashmemory,to previously saved settings, then restartsthe phone.

Press the Services, Settings, orDirectories button and then press**#**.

Restart phone


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Troubleshooting and MaintenanceGeneral Troubleshooting Tips for Cisco Unified IP Phone Expansion Module

ExplanationPerformingOperation

Resets user and network configurationsettings to their default values, deletes theCTL file from the phone, and restarts thephone.

From the Settingsmenu, unlock phoneoptions (see Unlock and LockOptions). Then press the Erasesoftkey.

Erase softkey

Resets network configuration settings totheir default values and resets the phone.This method causes DHCP to reconfigurethe IP address of the phone.

From the Network Configurationmenu, unlock phone options (seeUnlock and LockOptions). Then pressthe Erase softkey.

Deletes the CTL file from the phone andrestarts the phone.

From the Security Configurationmenu, unlock phone options (seeUnlock and LockOptions). Then pressthe Erase softkey.

Perform Factory ResetWhen you perform a factory reset of the Cisco Unified IP Phone, the following information is erased or resetto its default value:

• CTL file: Erased

• LSC: Erased

• User configuration settings: Reset to default values

• Network configuration settings: Reset to default values

• Call histories: Erased

• Locale information: Reset to default values

• Phone application: Erased. The phone recovers by loading the appropriate default load file(term62.default.loads, term61.default.loads, term42.default.loads, or term41.defaults.loads) dependingon the phone model.

Before you perform a factory reset, ensure that the following conditions are met:

• The phone must be on a DHCP-enabled network.

• A valid TFTP server must be set in DHCP option 150 or option 66 on the DHCP server.

• The default load file for your phone model and the files specified in that file should be available on theTFTP server that is specified by the DHCP packet.

To perform a factory reset of a phone, perform the following steps:

Procedure

Step 1 Unplug the power cable from the phone and then plug the cable back in.


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Troubleshooting and MaintenanceCisco Unified IP Phone Reset or Restore





The phone begins its power-up cycle.

Step 2 While the phone is powering up, and before the Speaker button flashes on and off, press and hold #.Continue to hold # until each line button flashes on and off in sequence in amber.

Step 3 Release # and press 123456789*0#.You can press a key twice in a row, but if you press the keys out of sequence, the factory reset will not takeplace.

After you press these keys, the line buttons on the phone flash red, and the phone goes through the factoryreset process.

Do not power down the phone until it completes the factory reset process, and the main screen appears.

Additional Troubleshooting InformationIf you have additional questions about troubleshooting the Cisco Unified IP Phones, these Cisco.comwebsitesprovide you with more tips.

• Cisco Unified IP Phone Troubleshooting Resources:

http://www.cisco.com/en/US/products/hw/phones/ps379/tsd_products_support_series_home.html

• Cisco Products and Services (Technical Support and Documentation):http://www.cisco.com/en/US/products/sw/voicesw/tsd_products_support_category_home.html

MaintenanceThis section includes the following topics

Quality Report ToolThe Quality Report Tool (QRT) is a voice quality and general problem-reporting tool for the Cisco Unified IPPhone. The QRT feature is installed as part of the Cisco Unified Communications Manager installation.

You can configure Cisco Unified IP Phones with QRT.When you do so, users can report problems with phonecalls pressing QRT. This softkey is available only when the Cisco Unified IP Phone is in the Connected,Connected Conference, Connected Transfer, or OnHook states.

When a user presses QRT, a list of problem categories appears. The user selects the appropriate problemcategory, and this feedback is logged in an XML file. Actual information logged depends on the user selection,and if the destination device is a Cisco Unified IP Phone.

For more information about using QRT, see the Cisco Unified Serviceability Administration Guide.


23

Troubleshooting and MaintenanceAdditional Troubleshooting Information

http://www.cisco.com/en/US/products/hw/phones/ps379/tsd_products_support_series_home.html

http://www.cisco.com/en/US/products/sw/voicesw/tsd_products_support_category_home.html

Voice Quality MonitoringTo measure the voice quality of calls that are sent and received within the network, Cisco Unified IP Phonesuse the following statistical metrics that are based on concealment events. The DSP plays concealment framesto mask frame loss in the voice packet stream.

• Concealment Ratio metrics: Shows the ratio of concealment frames over total speech frames. The phonecalculates an interval conceal ratio every 3 seconds.

• Concealed Second metrics: Shows the number of seconds in which the DSP plays concealment framesdue to lost frames. A severely “concealed second” is a second in which the DSP plays more than fivepercent concealment frames.

• MOS-LQK metrics: Uses a numeric score to estimate the relative voice listening quality. The CiscoUnified IP Phone calculates the mean opinion score (MOS) for listening quality (LQK) based audibleconcealment events due to frame loss in the preceding 8 seconds, and includes perceptual weightingfactors such as codec type and frame size.

The phone uses the Cisco proprietary algorithm, Cisco Voice Transmission Quality (CVTQ) index, toproduceMOSLQK scores. Depending on theMOSLQKversion number, these scoresmight be compliantwith the International Telecommunications Union (ITU) standard P.564. This standard defines evaluationmethods and performance accuracy targets that predict listening quality scores based on observation ofactual network impairment.

Concealment ratio and concealment seconds are primary measurements based on frame loss while MOSLQK scores project a “human-weighted” version of the same information on a scale from 5 (excellent) to1 (bad) for measuring listening quality.

Note

Listening quality scores (MOS LQK) relate to the clarity or sound of the received voice signal. Conversationalquality scores (MOS CQ, such as G.107) include impairment factors, such as delay, that degrade the naturalflow of conversation.

You can access voice quality metrics from the Cisco Unified IP Phone by using the Call Statistics screen orremotely by using Streaming Statistics.

Related Topics

Call Statistics ScreenRemote Monitoring

Voice Quality Metric InterpretationTo use the metrics for monitoring voice quality, note the typical scores under normal conditions of zero packetloss and use the metrics as a baseline for comparison.

It is important to distinguish significant changes from random changes in metrics. Significant changes arescores that change about 0.2 MOS or greater and persist in calls that last longer than 30 seconds. ConcealRatio changes should indicate greater than 3 percent frame loss.

MOS LQK scores can vary based on the codec that the Cisco Unified IP Phone uses.


24

Troubleshooting and MaintenanceVoice Quality Monitoring

The following codecs on the Cisco Unified IP Phones 7962G and 7942G provide these maximumMOS LQKscores under normal conditions with zero frame loss:

• G.711 gives 4.5

• G.722 gives 4.5

• G.728/iLBC gives 3.9

• G.729 A/AB gives 3.8

The following codecs on the Cisco Unified IP Phones 7961G/G-GE and 7941G/G-GE provide these maximumMOS LQK scores under normal conditions with zero frame loss:

• G.711 codec gives 4.5 score

• G.729A/ AB gives 3.7

Note • CVTQ does not support wideband (7 kHz) speech codecs, because ITU has not defined the extensionof the technique to wideband. Therefore, MOS scores that correspond to G.711 performance arereported for G.722 calls to allow basic quality monitoring, rather than not reporting an MOS score.

• Reporting G.711-scaleMOS scores for wideband calls through the use of CVTQ allows basic qualityclassifications to be indicated as good/normal or bad/abnormal. Calls with high scores (approximately4.5) indicate high quality/low packet loss, and lower scores (approximately 3.5) indicate lowquality/high packet loss.

• Unlike MOS, the Conceal Ratio and Concealed Seconds metrics remain valid and useful for bothwideband and narrowband calls.

A Conceal Ratio of zero indicates that the IP network is delivering frames and packets on time with no loss.

Voice Quality Troubleshooting TipsWhen you observe significant and persistent changes to metrics, use the following table for generaltroubleshooting information:

Table 4: Changes to Voice Quality Metrics

ConditionMetric change

Network impairment from packet loss or high jitter:

• Average MOS LQK decreases could indicate widespread and uniformimpairment.

• Individual MOS LQK decreases indicate bursty impairment.

Cross-check with Conceal Ratio and Conceal Seconds for evidence of packetloss and jitter.

MOS LQK scores decreasesignificantly


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Troubleshooting and MaintenanceVoice Quality Monitoring

ConditionMetric change

Check to see whether the phone is using a different codec than expected(RxType and TxType).

Check to see whether theMOSLQKversion changed after a firmware upgrade.

MOS LQK scores decreasesignificantly

• Network impairment from packet loss or high jitter.Conceal Ratio and ConcealSeconds increasesignificantly

Noise or distortion in the audio channel such as echo or audio levels.

Tandem calls that undergo multiple encode/decode, such as calls to a cellularnetwork or calling card network.

Acoustic problems coming from a speakerphone, handsfree cellular phone, orwireless headset.

Check packet transmit (TxCnt) and packet receive (RxCnt) counters to verifythat voice packets are flowing.

Conceal Ratio is near or atzero, but the voice quality ispoor.

Voice quality metrics do not account for noise or distortion, only frame loss.Note

Cisco Unified IP Phone CleaningTo clean your Cisco Unified IP phone, use a soft, dry cloth to wipe the phone screen. Do not apply liquids orpowders directly on the phone. As with all non-weather-proof electronics, liquids and powders can damagethe components and cause failures.

Disable the screen before cleaning it so that you will not inadvertently choose a feature from the pressure ofthe cleaning cloth. To disable the screen, press Display for more than one second. The phone displaysTouchscreen Disabled or Phone Screen Disabled and the Display button flashes green.

After one minute, the screen automatically reenables itself. To reenable the screen before that, press theflashingDisplay button for more than one second. The phone displaysTouchscreen Enabled or PhoneScreen Enabled.


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Troubleshooting and MaintenanceCisco Unified IP Phone Cleaning

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